Twin tube style dampers or shock absorbers are commonly used as part of a suspension system for automobiles, trucks, motorcycles, all-terrain vehicles (ATV), bicycles, industrial equipment and the like for absorbing and dissipating energy. A conventional twin tube type damper generally includes an inner fluid chamber that is at least partially defined by an inner tube, an outer fluid chamber defined by an outer tube that is in fluid communication with the inner fluid chamber, and a piston assembly that extends into the inner tube. Further, these components can be combined with a spring such as an air spring or a helical spring and conventionally referred to as a shock absorber. Certain twin tube style dampers also include a fluid reservoir that is in fluid communication with the inner and the outer fluid chambers via various fluid circuits. A damping fluid fills the inner and the outer fluid chambers and a portion of the fluid reservoir.
In many twin tube style dampers, the fluid reservoir is offset from other components of the damper, such as the chambers. Accordingly, fluid flow into such reservoir can be relatively inefficient, which can reduce the efficiency of the overall damper during operation. Additionally, the excess space utilized by the fluid reservoir can result in the damper being large and cumbersome. Some twin tube style dampers incorporate fluid reservoir features into the chambers, and may thus include for example rigid, movable walls or radially displaceable diaphragms. However, such features may still not provide optimal damper efficiency.
Accordingly, improved twin tube style dampers are desired in the art. In particular, twin tube style dampers which provide more efficient damping and less cumbersome geometry would be advantageous.